Solar energy collector

Abstract

A solar collecting apparatus for collecting solar energy in a heat transfer fluid includes an upper header member, a lower header member, and a plurality of collector tubes, each collector tube connected at an upper end thereof to the upper header member and connected at a lower end thereof to the lower header member. The collector tubes are arranged such that axes of the collector tubes form an array wherein no three adjacent axes are on the same plane, typically in a cylindrical or like array.

1. A solar collecting apparatus for collecting solar energy in a heat transfer fluid, the apparatus comprising:
 an upper header member; 
 a lower header member; 
 a plurality of collector tubes, each collector tube connected at an upper end thereof to the upper header member and connected at a lower end thereof to the lower header member; 
 wherein the collector tubes are arranged such that axes of the collector tubes form an array wherein no three adjacent axes are on the same plane; 
 a circulating tube connected at an upper end thereof to the upper header member and connected at a lower end thereof to the lower header member, wherein a diameter of the circulating tube is greater than a diameter of any collector tube, and wherein at least one of the upper and lower header members defines a port for connection to a fluid conduit; 
 wherein the circulating tube is connected to central portions of the upper and lower header members, and wherein the collector tubes are connected to outer portions of the upper and lower header members such that the circulating tube is substantially surrounded by collector tubes. 
 
   
   
     2. The apparatus of  claim 1  wherein the axes of the collector tubes form an array that is one of cylindrical, polygonal, and random. 
   
   
     3. The apparatus of  claim 1  wherein a line drawn from a first collector tube axis to a second collector tube axis and then to a third collector tube axis forms an obtuse angle at the second collector tube. 
   
   
     4. The apparatus of  claim 1  adapted to be mounted in a location exposed to solar rays such that the collector tubes are oriented substantially vertically. 
   
   
     5. The apparatus of  claim 1  wherein the collector tubes are configured to increase a surface area of the collector tubes. 
   
   
     6. The apparatus of  claim 5  wherein at least one collector tube includes at least one of fins, ridges, corrugations, pits, and recesses defined in one of the outer surface thereof and the inner surface thereof. 
   
   
     7. The apparatus of  claim 1  wherein the upper and lower headers are connected to a source of circulating fluid such that fluid flows into one of the upper and lower headers and out of the other of the upper and lower headers. 
   
   
     8. The apparatus of  claim 1  wherein a surface of the circulating tube is reflective. 
   
   
     9. The apparatus of  claim 1  wherein the lower header member is supported on a tank, and is connected to the tank such that water in the tank is heated by solar rays contacting the collector tubes. 
   
   
     10. The apparatus of  claim 1  further comprising a transparent shell enclosing the collector tubes and operative to retain heat inside an enclosure formed by the shell. 
   
   
     11. The apparatus of  claim 10  wherein the shell extends from the upper header down to the lower header to form the shell. 
   
   
     12. The apparatus of  claim 10  wherein air is evacuated from the enclosure. 
   
   
     13. A solar collecting apparatus for collecting solar energy in a heat transfer fluid, the apparatus comprising:
 an upper header member; 
 a lower header member; 
 a circulating tube connected at an upper end thereof to a central portion of the upper header member and connected at a lower end thereof to a central portion of the lower header member; 
 a plurality of collector tubes, each collector tube connected at an upper end thereof to an outer portion of the upper header member and connected at a lower end thereof to an outer portion of the lower header member; 
 wherein the collector tubes are arranged such that axes of the collector tubes form an array wherein no three adjacent axes are on the same plane, and such that the circulating tube is substantially surrounded by collector tubes; 
 wherein a diameter of the circulating tube is greater than a diameter of any collector tube, and wherein at least one of the upper and lower header members defines a port for connection to a fluid conduit. 
 
   
   
     14. The apparatus of  claim 13  wherein a surface of the circulating tube is reflective. 
   
   
     15. The apparatus of  claim 13  wherein the lower header member is supported on a tank, and is connected to the tank such that water in the tank is heated by solar rays contacting the collector tubes. 
   
   
     16. The apparatus of  claim 13  further comprising a transparent shell extending from the upper header down to the lower header to form the shell and operative to retain heat inside an enclosure formed by the shell. 
   
   
     17. The apparatus of  claim 16  wherein air is evacuated from the enclosure.